Quantifying Microvascular Abnormalities with Increasing Disease Severity in Diabetes Mellitus

Abstract

Purpose : To quantify retinal and choriocapillaris microvascular changes in healthy control eyes and different stages of diabetic retinopathy (DR) using optical coherence tomography angiography (OCTA).

Methods : This was a retrospective cross-sectional study including 44 eyes of 26 healthy age-matched controls and 137 eyes of 86 patients with different stages of DR. All participants were imaged with a commercial OCTA device (RTVue-XR Avanti, OptoVue Inc.). We analyzed the superficial (SCP) and deep retinal capillary plexus (DCP), the full retina as well as the choriocapillaris for the following OCTA parameters: foveal avascular zone, vessel density, percentage area of non-perfusion (PAN) and adjusted flow index (AFI). We included demographic and disease-related covariates into our statistical models.

Results : All OCTA parameters correlated significantly with DR severity (p<0.05) in the univariate models, however, when we corrected for covariates, only vessel density and PAN (all layers) and the AFI in the DCP remained significantly correlated with DR severity. There was no significant difference between healthy controls and eyes with DM without DR, although we found a borderline significant increase for AFI in the SCP (p= 0.0534).

Conclusions : Retinal and choriocapillaris vascular non-perfusion in OCTA is significantly correlated with disease severity in eyes with DR. Demographic and disease-related covariates as well as OCTA signal quality have a significant influence on the OCTA parameters and should be taken into account when using OCTA as an outcome measure in DR.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.